Wing Stands almost done - sort of....

Over the weekend I made pretty good progress on the Wing stands. As shown in this next pic, the support angles are now installed on both sets of stands. I am pleased with the way these have gone together. The Wing spar shown is actually sitting up side down from its correct resting position.

I have one more major step to complete before the spars will be ready to rest on the stands. This is the attach plate that must be affixed to the W712R end rib that serves as the outermost rib of the entire wing. The wing tip will be attached to the top and bottom wing skins adjacent to this final rib. One thing I learned from several other posts and discussions with other builders is that many do not take into account the position of the wing skins at the outermost edge of the wing. The skins will overlap the outer rib and end of the wing spar by about 3/4 of an inch, and a lot of folks attach the outer wing rib right up next to the main support bracket on the stand, only to find out later during installation of the skins that they need to reposition the spar or find some other solution to allow the additional room for the over-hanging wing skins.

So hopefully I have thought this through far enough in advance to know that I needed to obtain a large enough piece of angle to provide the necessary clearance between the end rib and the support angle bracket on the stand. The solution is a 2x2x1/8 inch piece of angle that will will be cut to a 5 inch length. One half of the angle will be positioned on the forward part of the W712R Wing rib adjacent to the wing spar web, and the other half of the angle lays over the top side of the support angle bracket. The 2 inch wide angle should provide enough clearance for the overhanging wing skins. Again, pictures of this will speak a thousand words, but here as an example once again is a shot of Sean Thomas' arrangement for this, and mine will be somewhat similar:

From the above pic I think that Sean will also have this problem when the time comes, because his rib is a bit too close to the support angle. Note the thick piece of angle (looks like 1/4 inch thick) that is bolted to the rib on the top left of this pic, and how it overhangs the main support angle bracket.

Next is a shot from the top side showing the rest of the angle that attaches to the main support angle bracket. The theme here is that only one side of the wing spar actually rests on the support angle on one side. The other side is affixed to the support angle bracket via an additional angle bracket attached to the end rib. The trick to all of this is getting the attachment angle properly positioned so that the spar can be maintained in a level attitude.

I have recently read some posts from other builders who have complained about the skins becoming slightly misaligned as they try to fit them together. I can't help but think that it has at least something to do with not maintaining as level an attitude as possible for the wing spar, which causes the skins and ribs to slant one way or the other. So the real critical part to this hole thing is to get the attachment angle positioned and bolted to the end rib in the just the right spot. Note the torpedo level in the pic below as well. You not only need to be level across the width of the spar, but also along the entire span of the spar.

And finally the pic of the bolts that attach the end rib to the attaching angle.

Meanwhile, back to a couple of shots of my build. It has been a very very long time since I assembled any of the actual airplane parts together. This is always one of many - "wow this is really cool!" moments in the build when you start to see the smaller parts become bigger airplane parts. The next step after getting the wing stands done is to cleco the main wing ribs to the spar and drill the attach holes to final size. It is also a preliminary check to see how well your ribs align perpendicularly with the spar. ON the right are the ribs that folks will be stepping on top of to get into and out of the airplane, and on the far left is the end rib discussed previously.

Lots of little steps remain on the way to completing each wing, but the fixture part of this process is almost over. Getting into another cold spell around here so I decided to take a break from the shop tonight. I hope to have both attachment angles positioned on both end ribs so I can proceed with the rest of the rib prep that is required before I can finally pound some rivets.